Power supplies for sensors often introduce unwanted and extraneous electrical noise affecting the output signal of a sensor. Consequently, since the output of the sensor contains noise, the sensor readings resulting from that output are similarly distorted due to that same electrical noise. One such error is that a “false detection” can occur, where the sensor produces data appearing to show a detection, but is actually displaying the electrical noise of the power supply.
Thus, filtering devices are often disposed between a sensor and its power supply. These devices are often designed to reduce or remove (i.e., filter) extraneous electrical noise introduced from a power supply and other sources thereby providing a cleaner power input to the sensor and thereby producing a more accurate output. Further, when the output is read into the sensor, the data input is cleaner (removing ‘false detections’) thereby producing better data.
Ultrasonic sensors can be arranged on a bumper of the motor vehicle and serve to detect objects in the surroundings of the motor vehicle. In order to be able to detect the objects, an ultrasound signal is emitted from the ultrasonic sensor during a transmission phase. For this purpose, a membrane of the ultrasonic sensor is excited with a corresponding transducer element, for example a piezoelectric element, to oscillate. In order to be able to operate the converter element during the transmission phase, comparatively high electrical currents are required. In a subsequent evaluation phase, the ultrasound signal reflected by the object is received again with the ultrasonic sensor. During the evaluation phase, the transducer element is not excited. In this case, the ultrasonic sensor is operated with a relatively low evaluation current or operating current.